package compare;

class A{}
class B extends A{}
interface X{}
interface Y extends X{}
class C implements X{}
class D implements Y{}

public class Inheritance {
	public static void main(String[] args) {
		A a = new A();
		A b = new B();
		
		X x = new C();
		X xd = new D();
		Y y = new D();
	
	}
}
